UVA - 568 Just the Facts-优快云博客

本文链接：https://blog.youkuaiyun.com/zz_FreeSky/article/details/38495563

本文介绍了一个程序设计问题，即如何计算任意非负整数阶乘后的尾部第一个非零数字。通过示例说明了输入输出的要求，并提供了一段C语言代码实现此功能。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

The expression N!, read as `` N factorial," denotes the product of the first N positive integers, where N is nonnegative. So, for example,

N	N!
`0`	`1`
`1`	`1`
`2`	`2`
`3`	`6`
`4`	`24`
`5`	`120`
`10`	`3628800`

For this problem, you are to write a program that can compute the lastnon-zero digit of anyfactorial for ( $0 \le N \le 10000$ ). For example, if your program is asked tocompute the last nonzerodigit of 5!, your program should produce ``2" because 5! = 120, and 2 is the last nonzero digit of 120.

Input

Input to the program is a series of nonnegative integers not exceeding 10000,each on its own linewith no other letters, digits or spaces. For each integer N, you shouldread the value and compute the last nonzero digit of N!.

Output

For each integer input, the program should print exactly one line ofoutput. Each line of outputshould contain the value N, right-justified in columns 1 through 5 withleading blanks, not leadingzeroes. Columns 6 - 9 must contain `` -> " (space hyphen greater space).Column 10 must contain the single last non-zero digit of N!.

Sample Input

Sample Output

    1 -> 1
    2 -> 2
   26 -> 4
  125 -> 8
 3125 -> 2
 9999 -> 8



 

#include<stdio.h>
int main()
{
    int n;
    while(scanf("%d",&n)!=EOF)
    {
        int s=1;
        for(int i=1;i<=n;i++)
        {
            int j=i;
            while(j%10==0)j/=10;
            s=s*j;
           
            while(s%10==0)s/=10;
            s=s%100000;
        }
        printf("%5d -> %d\n",n,s%10);
    }
return 0;
 }